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Stable Diffusion 3.5 Mediumvs.FLUX1.1 [pro]

Which one is better?

In our own test both are on par. Neither is in the arena. Neither has an API price.

Same prompt, two images

Same task, the first image of each. The task with the biggest difference is preselected.

Stable Diffusion 3.5 Medium: Character and detail, first image from the fixed test run
Stable Diffusion 3.5 Medium16 out of 100
FLUX1.1 [pro]: Character and detail, first image from the fixed test run
FLUX1.1 [pro]36 out of 100

Result for “Character and detail”:FLUX1.1 [pro] slightly ahead

Prompt given to both modelsCreate a square cinematic full-body portrait of a fictional bicycle courier waiting under a transparent umbrella at a rainy tram stop in Hamburg at blue hour. She wears a mustard raincoat, navy trousers, red sneakers, a silver helmet, and carries a teal messenger bag. Keep both hands visible, render the bicycle correctly, use realistic wet-street reflections, and include no readable brand names.

What the rating looks at: Anatomy, clothing, and spatial consistency.

“Ahead”: better in all three rating rounds. “Slightly ahead”: a higher value, but not in every round.

Test protocol of the images

Both models receive the same archived prompt in exactly one request, and the first result counts. Files are normalized to 1,024 × 1,024 pixels without cropping. Provider resolution, randomness, quality tier and prompt processing can still differ. The images are a practical visual test, not a reconstruction of the arena configuration.

Character and detail

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:17 PM. Source

FLUX1.1 [pro]: fal, requested 1024x1024, n=1, seed=1598804755, prompt expansion disabled, estimated cost $0.040000, generated Nov 1, 2026, 9:00 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: 985a75b38642a9f0e5e0c0e0c67f1b7f67780d42bd2168fa24e9a7a7a94b0da6

Stable Diffusion 3.5 Medium image SHA 256: 6b8aa732e94479ad302904096c5031908141e4083ee099f080185aa04c2ea800

FLUX1.1 [pro] image SHA 256: b475e58b4513d0ed851a405764c795b380f352ddff2599324a6ddf4046a2ca83

Infographic

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:17 PM. Source

FLUX1.1 [pro]: fal, requested 1024x1024, n=1, seed=2834891197, prompt expansion disabled, estimated cost $0.040000, generated Nov 1, 2026, 9:00 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: ed65cb4e6a51e2336f8b149ad4cbb16e020f07d527ad94362e719d2dcf91d94f

Stable Diffusion 3.5 Medium image SHA 256: 61b12e227431387098e51c6ce6d059be9d8df9c85263b994bee62602e2ddfd16

FLUX1.1 [pro] image SHA 256: 2e27914d8784b0c4df1bb786934c4269230e1b2a6657fa500cb3cf46c3244041

Product photography

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:16 PM. Source

FLUX1.1 [pro]: fal, requested 1024x1024, n=1, seed=1611870596, prompt expansion disabled, estimated cost $0.040000, generated Nov 1, 2026, 9:00 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: c67fd71e91304458a2feef5c91efa8677260fab0c0099a29a2c52cb579f5b2f3

Stable Diffusion 3.5 Medium image SHA 256: 2412a20e61c118ce7ab7ff83e285b96eb32d5c0f1171cc769e153db6655b8f67

FLUX1.1 [pro] image SHA 256: 4e45c833a1cfb178fdb2be4962709d5add987ae330bb860e739a934623327ad8

Typography and layout

Stable Diffusion 3.5 Medium: fal, requested 1024x1024, n=1, seed=provider random, estimated cost $0.020000, generated Nov 1, 2026, 9:16 PM. Source

FLUX1.1 [pro]: fal, requested 1024x1024, n=1, seed=22370095, prompt expansion disabled, estimated cost $0.040000, generated Nov 1, 2026, 9:00 PM. Source

Protocol gradually-image-comparison-v1. Prompt SHA 256: 2e012c3d14ee5dd02203a94f394ca80a5038cdebd6032b25a8b8a221f2255419

Stable Diffusion 3.5 Medium image SHA 256: bc854c3269ea8bada6f764545f4a09abedc110219018c09f2fa5708a14d9af7e

FLUX1.1 [pro] image SHA 256: 30f27d636afd6c596e3314f7412ca3a0497be81362e72e40fbf8d8517adb80ab

The numbers at a glance

Arena ratingfrom votes by users · higher is better
n/a

Stable Diffusion 3.5 Medium

not in the arena

n/a

FLUX1.1 [pro]

not in the arena

GraduallyBenchour own rating, 0 to 100 · higher is better
16

Stable Diffusion 3.5 Medium

Rank 69 of 74

25

FLUX1.1 [pro]

Rank 62 of 74

Price per imagedollars through the API · lower is better
n/a

Stable Diffusion 3.5 Medium

no API price

n/a

FLUX1.1 [pro]

no API price

Ranks among the 22 image models with an arena rating and the 74 with a GraduallyBench run; prices compared with 28 models with an API price.

Stable Diffusion 3.5 Medium

Subscription
n/a No plan in Germany names exactly this model.
Via API
No API price known. Access: API, local.
License
Open weights.

FLUX1.1 [pro]

Subscription
No Black Forest Labs subscription includes this model. Through other providers from ≈ €9.59 a month (Krea Basic, with limited credits). 14 plans in Germany.
Via API
No API price known. Access: API.
Weights
unknown.

Subscriptions only count plans that name exactly this model. Subscription prices include VAT, API prices are in dollars.

GraduallyBench from Nov 1, 2026 · Subscription database from Sep 29, 2026 (34 days old)

All data side by side

The better value is bold. For ratings only when the gap is clear.

KennzahlStable Diffusion 3.5 MediumFLUX1.1 [pro]
Ratings
Arena ratingfrom votes by users, higher is bettern/an/a
Arena rankn/an/a
Arena votesmore votes, a safer ratingn/an/a
GraduallyBenchour own rating, 0 to 1001625
GraduallyBench by task
Typography and layoutLegible text, hierarchy, and composition1724
Product photographyMaterials, reflections, and fine details1322
Character and detailAnatomy, clothing, and spatial consistency1636
InfographicNumbers, labels, and visual organization2017
API price
Per imagelower is bettern/an/a
100 imagesn/an/a
Profile
ReleasedOct 29, 2024n/a
Weightsopen means: runs locallyopenunknown
Lifecycleno noticeOlder, still documented BFL text-to-image API route
AccessAPI, localAPI
Parameters2.5 billionnot published
Largest outputnot consistently publishednot consistently published
Plans in Germanynaming exactly this modeln/a14

API prices for one image at 1,024 × 1,024 pixels according to Artificial Analysis.

Sources: Stable Diffusion 3.5 Medium model source (verified Nov 1, 2026) · FLUX1.1 [pro] model source, status source (verified Nov 1, 2026)

Arena ratings by category

From blind votes on LMArena. “Ahead” means the lead is clear.

No shared arena score in the stored snapshot

The stored benchmark database contains no measurement for Stable Diffusion 3.5 Medium and FLUX1.1 [pro] from the same arena and category. Older model versions are not used as substitutes.

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